Question

QUESTION 2.7

A solution is obtained by mixing 300 g of $25\%$ solution and 400 g of $40\%$ solution by mass. Calculate the mass percentage of the resulting solution.

Answer 1

Mass of solute in I solution $=\frac{25}{100}\times 300g=75g$

Mass of solute in II solution $=\frac{40}{100}\times 400=160g$

After mixing both solutions,

Total mass of solute = (75 + 160) g = 235 g

Total mass of solution = (300 + 400) g = 700 g

Mass $\%$ of solute in final solution $=\frac{\left(235g\right)}{\left(700g\right)}\times 100=33.57\%$

Mass $\%$ solvent in final solution $=100-33.57=66.43\%$